1. Field of the Invention
This invention relates to new and useful improvements in packaging, and, more particularly, to packaging which inhibits bacterial activity in the material packaged and on the surface of the packaging material.
2. Brief Description of the Prior Art
The prior art discloses a number of examples of plastic film or sheet packaging materials which contain small amounts of biocidal materials for preventing bacterial attack on the film itself. This prior art, however, does not show the use of biocidal materials in packaging films or sheets at a level such that the contents of a package made therefrom are inhibited against bacterial or viral growth.
LIU et al U.S. Pat. No. 4,617,328 discloses that cellulosic, plastics, or film-forming polymer compsns. which are made up in continuous form are protected against attack by bacteria, fungi and antinomycetes by incorporating into the compsn. (or continuous form) or by coating with various known agricultural, microbicides, bactericides and paint preservatives. They can be fabricated into a continuous form against attack by bacteria, fungi or actinomycetes, are thermally stable at more than 148 deg. C. without deterioration, are able to migrate through compsn. to be dissipated throughout, and are stable towards ultraviolet and other light radiation. Compounds having formula: Y-(1,4-phenylene)-SO2-CH.dbd.CH--CN, in which Y is hydrogen, halogen, or C1-C4 alkyl; R1 AND R2 are independently hydrogen or methyl; and N is 1 or 2, are effective biocides or biostats for protection of plastic, polymeric or cellulosic materials against attack by microorganisms.
Gutman et al U.S. Pat. Nos. 4,388,249 and 4,331,480 disclose that compounds of the formula: EQU (NC--HC.dbd.CH- O2S-),(R-O-)M,(X-)N- benzene
in which R is lower alkyl; X is halogen or lower alkyl; M is 1 OR 2; and N is 0, 1, 2 OR 3, are effective biocides or biostats for protection of plastic or polymeric materials against attack by microorganisms.
Rei U.S. Pat. Nos. 4,661,528 and 4,663,359 disclose a composition comprising a dry blend mixture of a porous thermoplastic resin powder and from 1 to 80 wt. % of a microbiocide based upon the weight of the mixture. The microbiocide is present in the mixture at a concentration of at least about 20 times greater than the normal upper usage concentration of the microbiocide, and is held within the pores of the thermoplastic powder. The resulting concentrate is a substantially non-dusting, freeflowing powder which is readily incorporated into a second thermoplastic resin to product a resulting article having the appropriate level of microbiocide. The resin is polyvinyl chloride, polyethylene, polystyrene, polypropylene, nylon, styrenebutadiene copolymer, polycarbonate, polystyrene-polyphenylene oxide blend, polyphenylene oxide or an ethylene/acrylic acid salt ionomer. The microbiocide is 10,10'-oxybisphenoxarsine; N(trichloromethylthio)-4-cyclohexene-1,2-dicarboxinide; 2,3,5 trichloro-4-propylsulfo 2,3,4,5-tetrachloro-4(methylsulfonyl)pyridine; zinc salt of 1-hydroxypyridine-2thione; N-(trichloromethylthio)phthalimide; N-(2methylnaphthyl)meleimide; cis-N-(1,1,2,2-tetrachloroethyl-thio4-cyclohexene-1,2-dicarboximide; 1-isopropyl-3-methyl pyrazolyl-5-dimethyl carbamate; 3-,ethyl pyrazoyl dimethylcarbamate; manganese ethylene bisdithiocarbamate; zinc ethylene bisdithiocarbamate; disodium ethylene bisdithiocarbamate; ferric dimethyl dithiocarbamate; zinc dimethyl dithiocarbamate; 2,4-dinitro-6-capryl phenol crotonate; p-chlorophenyl-p-chlorobenzene sulfonate; 2-N-octyl-4-isothiazol in-3-one; methyl(butyl carbamoyl)-2-benzimidazole carbamate; 2-(4thiazole) benzimidazole; copper 8-hydroxylquinolinate; alpha-diethoxyphosphinodithioacetylurea; alpha dimethoxylphosphinodithioacetylurea; diethoxyphosphinodithioacetamide dimethoxyphosphinodithioacetamide; bis(dimethylamido)phosphoryl fluoride; 2-cyclohexyl-3-isothiazolone; 4,5-dichloro-2cyclohexyl-3-isothiazolone or tributyl tin fluoride.
Hill et al U.S. Pat. No. 4,086,297 discloses that a solid composition comprising a homogeneous mixture of a solid thermoplastic resin and from 1 to 80 weight % of a microbiocide which is insoluble in water is readily dispersible or soluble in the resin at temperatures sufficiently high to permit plastic manipulation of the resin and the dispersion or solution of the microbiocide is sustained indefinitely upon cooling to ambient temperature while the diffusivity of the microbiocide in the resin under such conditions becomes vanishingly small, retains its microbiocidal activity in the resin and does not degrade or react with the resin in which it is dispersed. This composition provides a convenient nontoxic dosage from of the microbiocide which is subsequently mixed with a second thermoplastic resin at a concentration of about 0.5 to 15 weight % to obtain a homogeneous resin composition containing an effective amount of the microbiocide.
Pupp U.S. Pat. No. 4,461,667 discloses a packing material for aseptic packages having the interior coated with polyethylene and extruded to give a separable, bacteria tight package.
Knopick et al U.S. Pat. No. 4,164,941 discloses a disposable drape for a surgical overhead table where the drape is liquid-proof and covers the entire surface of the associated table. Also, the drape is of a construction which will prevent the passage of any bacteria through the surface area of the drape.
Several publications are also pertinent to the use of biocidal agents in plastic materials for protection of the material against degredation:
Inoue, Mayumi (Ventron Biocide Res. Inst., Japan) in JOURNAL: Bokin Bobai (1978) VOL. 6 NO. 6, pp. 250-7 reviews vinyzene antimicrobial plastics.
FLEXIBLE STERILE CLOSURE SYSTEM FOR CONTAINERS INHIBITING BIOSLIMES ON SURFACES OF POLYETHYLENE TUBING, Ford, H. W.; Altermatt, W. E.; Hamilton, N. F. Univ of Florida, Lake Alfred, FL, USA Drainage Design and Management, Proceedings of the Fifth National Drainage Symposium Chicago, IL, Dec 14-15, 1987 Sponsored by: ASAE, St. Joseph, MI, U.S.A.; American Soc of Agronomy, Madison, WI, USA; ASCE, New York, N.Y., U.S.A.; Corrugated Plastic Tubing Assoc; Corp Science Soc of America, Madison, WI, U.S.A.; et al E.I. Conference No.: 11232 Source: ASAE Publication 07-87. Publ. by ASAE, St. Joseph, MI, USA p 416-423 (1987): A new approach for the control of microbial-induced clogging of plastic drain pipes involves incorporating an antimicrobial compounds into the resin at the time of manufacture of the drain tubing. Any compound added to polyethylene for drain pipe applications to inhibit bioslimes must be compatible with the resin system and have stable properties when in contact with soil and water. Slow release of the antimicrobial compound would provide the required long-term performance. The treated pipe must be safe for surface water and control ochre when applied at EPA-approved treatment levels. In the studies described in this paper, Vinyzene (REGISTERED) SB-1 PR, was used as the biocide in polyethylene materials. Bio-Flow is the name for SB-1 PR incorporated in a specially designed orange-colored pipe containing 4. 7 and 12. 5 cm holes. Laboratory tests, simulated drain experiments, and the results of 30 months of field testing are described.
Kirk-Othmer Encyclopedia, chapter on Industrial Antimicrobial Agents: Arsenicals. 10,10'-Oxybisphenoxyarsine is the only organoarsenic product of importance as an industrial antimicrobial agent. The active ingredient is a colorless microcrystalline powder, but it is sold only in dilute formulations to minimize toxicity. Vinyzene solutions are used primarily for the plastic industry; Vinyzene is sold at 1% or 2% concentration in various plasticizers, eg, epoxidized soybean oil and various phthalate esters (qv), and at 5% as a pelletized solid polymeric resin (81). A 1% solution in 1,4-butanediol is provided for use in polyurethanes (88). The Durotex solution that is used in the textile industry is 2% active and is formulated with nonionic, cationic, or anionic emulsifiers (82). Although many arsenic compounds are generally recognized as being toxic, the 10,10-oxybisphenoxyarsine products are claimed to be less toxic because the arsenic is organically bound. Nonetheless, when undiluted, the active ingredient is a skin and eye irritant; however, the products are diluted in order to minimize toxicity (see Arsenic compounds).